Can't establish LDP session between two Mikrotik routers

RouterOS Forwarding Protocols
1

Hello, I’m implementing a new MPLS lab network with the following topology:

I am to the beginning of the config. IP and OSPF has been configured on all nodes and all MPLS routers can reach each other on both loopback and link IPs. From that point, I started configuring LDP on the two mikrotik routers with the following config:

[admin@MikroTik-LSR] /mpls> export
/mpls ldp
set enabled=yes transport-address=100.0.0.3
/mpls ldp interface
add interface=ether1
add interface=ether2

[admin@MikroTik-PE] /mpls> export
/mpls ldp
set enabled=yes transport-address=100.0.0.4
/mpls ldp interface
add interface=ether2

However, they don’t establish a LDP session (mpls ldp neighbor print shows nothing). I followed the MPLS VPN from the mikrotik wiki and I can’t figure out what I’m doing wrong. Configured interfaces are shown under LDP, IP are reachable, etc…

[admin@MikroTik-LSR] /mpls> ldp interface print
Flags: X - disabled, I - invalid
 #   INTERFACE                                                           HELLO-INTERVAL       HOLD-TIME
 0 I ether1                                                              5s                   15s
 1 I ether2                                                              5s                   15s
 
 [admin@MikroTik-PE] /mpls> ldp interface print
Flags: X - disabled, I - invalid
 #   INTERFACE                                                         HELLO-INTERVAL       HOLD-TIME
 0 I ether2

Any idea what am I doing wrong? Thank you in advance for your help.

2

LDP interface configuration is invalid. Are those interfaces slaves? if yes then you need to add master.

3

Yes, they are all slaves.

[admin@MikroTik-PE] /interface ethernet> print
Flags: X - disabled, R - running, S - slave
 #    NAME                                MTU MAC-ADDRESS       ARP             SWITCH
 0 RS ether1                             1500 74:4D:28:46:6A:EB enabled         switch1
 1 RS ether2                             1500 74:4D:28:46:6A:EC enabled         switch1
 2 RS ether3                             1500 74:4D:28:46:6A:ED enabled         switch1

I run version 6.42.11 and 6.43.9. All my interface all linked to the default bridge:

/interface bridge port
add bridge=bridge comment=defconf interface=ether2
add bridge=bridge comment=defconf interface=ether3
add bridge=bridge comment=defconf interface=ether4
add bridge=bridge comment=defconf interface=ether5
add bridge=bridge comment=defconf interface=ether6
add bridge=bridge comment=defconf interface=ether7
add bridge=bridge comment=defconf interface=ether8
add bridge=bridge comment=defconf interface=ether9
add bridge=bridge comment=defconf interface=ether10
add bridge=bridge comment=defconf interface=sfp1
add bridge=bridge interface=ether1
4

So you answered your question yourself. Remove ether2 from the bridge and it should work.
-Chris

5

But if I remove an interface from the bridge, I loose connectivity to that interface. This is why I always add all interface to the default bridge.

6

You will have mpls connectivity on this interface.

7

I tried to remove ether2 from the bridge on my two Mikrotik router. There is no more IP connectivity neither OSPF, and there is still no LDP ajacency between the neighbor. However, ether2 is not showed anymore as “invalid”.

[admin@MikroTik-LSR] /mpls ldp> interface print
Flags: X - disabled, I - invalid
 #   INTERFACE                                                           HELLO-INTERVAL       HOLD-TIME
 0 I ether1                                                              5s                   15s
 1   ether2                                                              5s                   15s

In the Mikrotik world, if an Interface is attached to a bridge, this become a L2 port?

8

As I mentioned in my previous post. If you are adding interfaces which are part of the bridge, then LDP interface should be “bridge”, not a slave.